Jacks define female electrical connectors having a nonconductive housing and electrically conductive terminals therein. The jack typically is mounted to a circuit board, panel or the like, with the terminals in the jack being electrically connected to conductive areas on the circuit board or panel. The jack is mateable with a male plug connector which also has a nonconductive housing and a corresponding number of electrically conductive terminals. The plug frequently will be mounted to a cable having a plurality of electrically conductive leads which are respectively connected to the terminals in the plug. The cable leading to the plug may define a round cable or a flat flexible cable depending upon the particular application.
The combination of jacks and mateable plugs are used in many electrical devices, with broad applications being found in computers and telecommunications equipment. In most such applications it is necessary to shield signal carrying circuits to avoid generating electromagnetic interference (EMI), and/or to avoid being impacted by ambient EMI. In particular, the signal carrying cables leading to the above described plug typically will comprise an electrically conductive shield, such as a braid or a foil, extending around the signal carrying conductors of the cable. The plug to which the cable is connected also will comprise an electrically conductive shield extending thereabout and in electrical contact with the shield of the cable.
The jack will include its own shield which will be grounded to the board on which the jack is mounted. The typical shield for the prior art jack is mounted to the exterior of the jack housing, and comprises solder tails or other such board contact means unitary therewith and disposed to be electrically connected to grounds on the board. The shield of the prior art jack comprises contact means extending into the plug receiving cavity of the prior art jack. The contact means of the shield for the prior art jack are disposed to electrically contact the shield of the above described plug.
The prior art includes many variations to the above described shielded jacks. For example, many prior art jacks dispose the shields primarily on the front mating face of the jack with spring fingers extending into the plug receiving cavity of the jack for electrical grounding connection to the shield on the plug inserted into the plug receiving cavity of the jack. The grounding connection between the shielded jack and the board on which the jack is mounted is generally achieved by solder tails or other such board grounding contact means extending from the external portion of the prior art shield. An example of such a prior art shield is shown, for example, in U.S. Pat. No. 4,493,525 which issued to Hall et al. on Jan. 15, 1985.
Many shielded jacks include both internal and external shields. For example, an internal shield may substantially surround the terminals in the jack housing, while an external shield may surround at least portions of the external surfaces of the jack housing. A prior art shielded jack of this general type is shown in U.S. Pat. No. 4,637,669 which issued to Tajima on Jan. 20, 1987. The internal and external shields shown in U.S. Pat. No. 4,637,669 are electrically connected to one another and are then grounded to the board.
It is believed that in many of the prior art shielded jack constructions, the interconnected internal and external shields and/or the large grounding structures on the front mating face of the jack may actually function as antennas that can exacerbate EMI problems.
Electrical components have undergone remarkable miniaturization in recent years. As a result of this ongoing miniaturization, the density of circuits and components mounted to a circuit board has increased dramatically. This continuing trend toward component miniaturization and greater circuit density has created a very substantial demand for electrical connectors that achieve a lower profile and/or that occupy a smaller surface area or "footprint" on the board. Even small reductions in a connector's profile or footprint generally are greeted with significant commercial success. Particularly desirable connectors are those that can provide a lower profile or a smaller footprint while still being mateable with an accepted and standarized electrical connector plug.
It is also well known that the electrical connector industry is extremely competitive and cost conscious. Connectors that can achieve a specified function at a slightly lower cost can be particularly advantageous.
Accordingly, it is an object of the subject invention to provide a low profiled shield for an electrical connector jack.
It is another object of the subject invention to provide a low profile shielded jack.
It is an additional object of the subject invention to provide an EMI shield and a corresponding shielded jack that can be manufactured with substantially less metal and that achieve corresponding cost advantages.
A further object of the subject invention is to provide a low cost, low profile shielded jack that can be employed with a specified footprint on a circuit board.
An additional object of the subject invention is to provide a low profile shielded jack that is mateable with a standardized shielded plug connector.
Still a further object of the subject invention is to provide a shielded jack wherein substantially all of the shielding is disposed at interior locations on the jack.
Yet another object of the subject invention is to provide a shielded electrical connector wherein the components are easy to manufacture and to assemble.